True or False:

Hyperkalemia increases aldosterone secretion.

True

What is the secretion of aldosterone mainly controlled by?

- angiotensin II- potassium concentration

Which layer of the adrenal cortex is aldosterone (mineralocorticoids) secreted by?

zona glomerulosa

80

Look over slide 29 in the review well.

Decrease in blood volume mechanism for aldosterone synthesis and secretion.

81

What hormone is the major glucocorticoid?

Cortisol is major glucocorticoid.

82

What response is cortisol essential for?

Stress Response

83

What hormone released from the anterior pituitary mainly controls the secretion of cortisol?

ACTH

- ACTH up-regulates it own receptor. - Under the influence of CRH (corticotropin-releasing hormone) from neurosecretory cells located in the paraventricular nuclei. - Second messenger for both CRH and ACTH is cAMP.

Look over figure 80-7 on slide 45 of the review.

Vitamin D synthesis.

Where is the active form of vitamin D synthesized?

Kidney - under the control of PTH.

calcium

*by increasing, over a period of about 2 days, formation of calbindin, a calcium-binding protein, in the intestinal epithelial cells > this protein functions in the brush border of the epithelial cells to transport calcium into the cell cytoplasm

* then the calcium moves through the basolateral membrane of the cell by facilitated diffusion

* calbindin remains in the cell for weeks after the 1,25-dihydroxycholecalciferol has been removed from the body

111

How does 1,25-dihydroxycholecalciferol itself promote intestinal absorption of calcium?

By increasing, over a period of about 2 days, formation of calbindin, a calcium-binding protein, in the intestinal epithelial cells.

**this protein functions in the brush border of the epithelial cells to transport calcium into the cell cytoplasm**

112

What is the function of calbindin?

This protein functions in the brush border of the epithelial cells to transport calcium into the cell cytoplasm.

113

Calbindin functions in the brush border of the epithelial cells to transport calcium into the cell cytoplasm. By what type of diffusion does calcium move through the basolateral membrane of the cell?

facilitated diffusion

114

Does the preganglionic sympathetic or postganglionic sympathetic fibers pass through the white rami?

preganglionic sympathetic fiber

115

Does the preganglionic sympathetic or postganglionic sympathetic fibers pass through the gray rami?

postganglionic sympathetic fiber

116

What type of fibers are postganglionic sympathetic fibers classified as?

type C fibers

117

True or False:

Preganglionic fiber can pass for variable distances through the chain and then through one of the sympathetic nerves to synapse in a peripheral sympathetic ganglion.

True

118

True or False:

Preganglionic fibers can synapse with postganglionic neurons upward or downward in the paravertebral chain.

True

119

What percentage of fibers in the average nerve consist of postganglionic sympathetic fibers?

8%

120

What do postganglionic sympathetic fibers control?

- blood vessels - sweat glands- piloerector muscles

121

What are splanchnic nerves composed of?

- preganglionic fibers - visceral sensory fibers

122

What do splanchnic nerves supply?

abdominal viscera

123

Where do splanchnic nerves synapse?

prevertebral ganglia

124

From what thoracic vertebrae does the greater splanchnic nerves arise from?

T5-T9

125

From what thoracic vertebrae does the lesser splanchnic nerves arise from?

T10-T11

126

From what thoracic vertebra does the least splanchnic nerve arise from?

T12

127

What are the 3 splanchnic nerves?

- greater - lesser - least

128

Where does the greater splanchnic nerve synapse?

celiac ganglion

129

Where does the lesser splanchnic nerve synapse?

superior mesenteric ganglion

130

Where does the least splanchnic nerve synapse?

aorticorenal ganglion

131

In which cranial nerve is about 75% of all parasympathetic fibers in?

Vagus Nerve (CN X)

132

True or False:

Most preganglionic fibers pass all the way to the organ that is to be innervated.

True

133

What neurotransmitter is used by postganglionic parasympathetic fibers?

From which amino acid is norepinephrine derived from?

Tyrosine

What are the ways in which norepinephrine is removed?

Where is catechol-O-methyl transferase (COMT), which destructs norepinephrine to remove it, present?

present in all tissues

152

Where is monamine oxidase, which destroys norepinephrine, found?

in nerve endings

153

True or False:

Norepinephrine/epinephrine is active for only a few seconds when secreted directly into the tissues but when secreted into the blood (via the adrenal medulla) it remains active until destroyed by COMT in surrounding tissues, especially the liver.

True

154

What are the two types of acetylcholine receptors?

- muscarinic - nicotinic

155

Where are muscarinic (acetylcholine) receptors found?

On all effector cells stimulated by postganglionic cholinergic neurons.

156

Where are nicotinic (acetylcholine) receptors found?

In autonomic ganglia at synapses between preganglionic and postganglionic neurons.

Present in neuromuscular junctions in skeletal muscles.

157

Which class of adrenergic receptors does norepinephrine mainly excite?

Norepinephrine excites mainly alpha receptors but also beta receptors to a lesser extent.

158

True or False:

Epinephrine excites both alpha and beta adrenergic receptors almost equally.

- Responsible for increase in protein formation and muscle formation.

- Responsible for increase in bone matrix and calcium retention.

- Responsible for increased BMR.

- Responsible for increased hematocrit.

- Increases reabsorption of sodium in distal kidney tubules.

191

Where are sertoli cells located?

Within the seminiferous tubules.

192

What cell type is located within the seminiferous tubules?

Sertoli Cells

193

What is the function of sertoli cells?

Act as nurse cells (sustentacular cells) that surround primary spermatocytes and "nurse" them through the process of spermatogenesis and spermiogenesis (differentiation of spermatids into mature sperm).

Form estrogens from testosterone (thought to be important for spermiogenesis).

194

Where are cells of Leydig found?

In interstitial spaces in testes.

195

What cell is found in the interstitial spaces in testes?

cells of Leydig

196

What do cells of Leydig secrete?

testosterone

197

Which hormone secreted by the anterior pituitary stimulates the cells of Leydig to secrete testosterone?